HI
Rusty,
Been think (always
a bad idea in my case) about your concern of heating the air before the
radiator (if installed in the outflow area). While there is no
question there would be some heating by such things as the turbo, etc.
I am not certain that it would significantly effect the air temperature,
particularly in flight.
Heres what my rational is based
on. A single GM evaporator core that we use calculates out to having
approx 7000 square inches (actually a bit more) of surface area (fins
and tubes) thats approx 48 square feet of surface area for one
core. From whats been reported the air temp rise through a
core is approx 20-30F getting rid of all the coolant heat the engine needs
to have rejected
Now you wouldn't want air 30F higher
than ambient going into your rear mounted radiator, but I'll bet if you
estimated the surface area of your turbo and other significant heat
generators that you won't come up with anywhere near 48 square feet.
Furthermore if you shield the worst heat producer (your turbo and exhaust),
I would imagine you might find your air temp not increasing that much before
it reaches your radiator.
I intitially was concerned about the
same type of thing. I felt that if I ducted the rear of my radiators
to my side louvers that would keep the hot air from "reheating" the
engine. Well, it seemd to actually make matters worst (I suspect the
ducts were restricting the expanding hot air coming out of the
radiators). Tracy Crook convinced me that the additional heat content
(as opposed to temperature) blowing over the engine was insignificant in
adding to the heat load. Removed the outlet ducts and overall cooling
improved.
So if you do add ducts to get the air
from your inlet to the rear, just try to make certain that the ducts help
rather than hurt.
No calculations, just a gut feeling
which of course could be incorrect.
Ed
Anderson